U.S. patent application number 10/594078 was filed with the patent office on 2008-01-24 for method and apparatus for detecting the presence of a prescribed heat exchanger.
This patent application is currently assigned to DaimlerChrysler AG. Invention is credited to Michael-Rainer Busch, Dirk Herbstritt, Andreas Miksch.
Application Number | 20080021631 10/594078 |
Document ID | / |
Family ID | 34964671 |
Filed Date | 2008-01-24 |
United States Patent
Application |
20080021631 |
Kind Code |
A1 |
Busch; Michael-Rainer ; et
al. |
January 24, 2008 |
Method and Apparatus for Detecting the Presence of a Prescribed
Heat Exchanger
Abstract
A method and apparatus for detecting the presence of a
prescribed heat exchanger, such as a catalytically active radiator,
in a motor vehicle are performed, during operation of the motor
vehicle. The temperature of a heat-exchanger medium is observed
together with further current operationally relevant parameters of
the motor vehicle for a prespecified time window. An expected
temperature gradient over time of the heat-exchanger medium is
detected, as well as the current temperature gradient over time of
the temperature of the heat-exchanger medium. The presence of a
prescribed heat exchanger is detected taking into account the
expected temperature gradient and the current temperature
gradient.
Inventors: |
Busch; Michael-Rainer;
(Ebersbach, DE) ; Herbstritt; Dirk; (Durmersheim,
DE) ; Miksch; Andreas; (Stuttgart, DE) |
Correspondence
Address: |
CROWELL & MORING LLP;INTELLECTUAL PROPERTY GROUP
P.O. BOX 14300
WASHINGTON
DC
20044-4300
US
|
Assignee: |
DaimlerChrysler AG
Epplestrasse 225
Stuttgart
DE
70567
|
Family ID: |
34964671 |
Appl. No.: |
10/594078 |
Filed: |
March 23, 2005 |
PCT Filed: |
March 23, 2005 |
PCT NO: |
PCT/EP05/03095 |
371 Date: |
June 19, 2007 |
Current U.S.
Class: |
701/114 ;
165/11.1; 374/141 |
Current CPC
Class: |
F28F 2265/00 20130101;
F01P 11/14 20130101; B01D 53/88 20130101; F01P 11/00 20130101; B01D
53/9495 20130101; B01D 53/885 20130101 |
Class at
Publication: |
701/114 ;
165/011.1; 374/141 |
International
Class: |
F01P 11/14 20060101
F01P011/14; F28F 99/00 20060101 F28F099/00 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 26, 2004 |
DE |
10 2004 015 044.3 |
Claims
1.-16. (canceled)
17. A method for detecting presence or absence of a prescribed heat
exchanger in a motor vehicle, comprising the following steps which
are performed during operation of the motor vehicle: (S1) observing
temperature of a heat-exchanger medium and at the same time
observing further current operationally relevant parameters of the
motor vehicle for a given time window; (S2) determining an expected
time gradient of the temperature of the heat-exchanger medium; (S3)
determining a current time gradient of the temperature of the
heat-exchanger medium; and (S4) detecting the presence of a
prescribed heat exchanger based on the expected and the current
time gradients of the temperature of the heat-exchanger medium.
18. The method as claimed in claim 17, wherein method step (S1)
comprises the following substeps: (S1-1) measuring values of the
temperature of the heat-exchanger medium in predefined time
intervals and plotting the time profile of these values; and (S1-2)
measuring values of the operationally relevant parameters at
predefined time intervals and plotting the time profiles of these
values.
19. The method as claimed in claim 18, wherein method step (S2)
comprises the following substeps: (S2-1) comparing the plotted
current operationally relevant parameters with predefined values;
(S2-2) determining an associated current operating state in
accordance with this comparison; and (S4-1) comparing the current
and expected time gradients of the temperature of the
heat-exchanger medium; (S4-2) taking into account this comparison
result with reference to a predefined threshold value; (S4-3)
incrementing at least one counter in accordance with the comparison
result from substep (S4-2); (S4-4) carrying out method steps (S1)
to (S4) until a predefined counter reading is reached; and (S4-5)
outputting data signals when a prescribed heat exchanger is
present.
23. The method as claimed in claim 17, wherein: the time window is
determined to begin at a first time when at least one operationally
relevant parameter reaches a predefined starting threshold value;
and (S2-3) determining the temperature gradient expected in this
current operating state.
20. The method as claimed in claim 17, wherein the current
temperature gradient is detected in method step (S3) based on the
current values of the temperature of the heat-exchanger medium in
the time window.
21. The method as claimed in claim 17, wherein method step (S4)
comprises the following substeps: (S4-1) comparing the current and
expected time gradients of the temperature of the heat-exchanger
medium; (S4-2) taking into account this comparison result with
reference to a predefined threshold value; and (S4-3) transmitting
data signals when a prescribed heat exchanger (2) is present.
22. The method as claimed in claim 17, wherein method step (S4)
comprises the following substeps: the time window is determined to
end at a second time when the same or at least one further
operationally relevant parameter reaches the same or a further
predefined ending threshold value.
24. An apparatus for detecting the presence of a prescribed heat
exchanger in a motor vehicle, comprising: at least one heat
exchanger with a heat-exchanger medium of the motor of the motor
vehicle; at least one measuring device for measuring the
temperature of the heat-exchanger medium; and an evaluation device
for evaluating data and for detecting the presence of a prescribed
heat exchanger.
25. The apparatus as claimed in claim 24, wherein the measuring
device comprises: at least one temperature sensor for measuring the
temperature of the heat-exchanger medium; a holding element for
holding the temperature sensor; and a connection device for
connection to the evaluation device.
26. The apparatus as claimed in claim 25, wherein the holding
element is connected to the heat exchanger in a non-releasable
manner.
27. The apparatus as claimed in claim 25, wherein the holding
element for holding the temperature sensor has a holder which
corresponds to said temperature sensor.
28. The apparatus as claimed in claim 25, wherein the temperature
sensor has a predetermined breaking point and is connected to the
holding element such that it is rendered permanently inoperable
after it is removed from the holding element.
29. The apparatus as claimed in claim 25, wherein the temperature
sensor is a constituent part of an adapter of the connection
device.
30. The apparatus as claimed in claim 25, wherein the adapter and
the holding element have corresponding fastening elements which are
designed such that they cannot be released following assembly.
31. The apparatus as claimed in claim 24, wherein the evaluation
device comprises: a memory device for storing values of time
profiles of measured values; a data memory for storing predefined
threshold values, operating state data and other data; and at least
one counter.
32. The apparatus as claimed in claim 31, wherein the evaluation
device is a constituent part of an on-board computer of a motor
vehicle.
33. The apparatus as claimed in claim 24, wherein said evaluation
device comprises a processor which is programmed to: determine an
expected time gradient of measured temperature of the
heat-exchanger medium; determine a current time gradient of said
measured temperature of the heat-exchanger medium; and detect
presence of a prescribed heat exchanger based on said expected and
current time gradients.
Description
BACKGROUND AND SUMMARY OF THE INVENTION
[0001] This application claims the priority of German patent
document 10 2004 015 044.3, filed Mar. 26, 2004 (PCT International
Application PCT/EP205/003095, filed Mar. 23, 2005), the disclosure
of which is expressly incorporated by reference herein.
[0002] The invention relates to a method for detecting the presence
of a prescribed heat exchanger, in particular a catalytically
active radiator in a motor vehicle, and to an apparatus for this
purpose which has at least one heat exchanger, at least one
measuring device, and an evaluation device.
[0003] So-called catalytically active radiators are frequently
provided in modern motor vehicles. A catalytically active radiator
for the coolant of a vehicle motor has an additional coating which
catalytically converts ozone that is present in the air which onto
the vehicle and flows through the radiator, into harmless oxygen.
Such catalytically active radiators are sometimes also known by the
trade name "PremAir radiator.TM.". Catalytically active radiators
of this type have been developed particularly with regard to better
environmental compatibility of the materials used and to avoid the
undesired ozone, and therefore often satisfy the corresponding
relevant environment regulations.
[0004] In many countries, the use of a catalytically active
radiator in a motor vehicle is subject to special statutory
regulations. In particular, tax benefits are often granted when
such radiator elements are used since these radiators have a lesser
effect on the environment on account of the conversion of harmful
ozone into atmospheric oxygen. However, such radiator elements are
relatively expensive, which often offsets the advantage of the tax
saving. As a result, there is an incentive to replace the expensive
radiator in the motor vehicle (which results in a tax saving), with
a comparatively low-cost radiator under certain circumstances. It
is therefore necessary to ensure that an installed catalytic
radiator cannot be exchanged for a conventional radiator without
activation of a safety unit (for example, an on-board diagnosis
(OBD) system). That is, the comparatively expensive radiators
should therefore be protected against adulteration and
manipulation.
[0005] European patent document EP 1 153 646 A1 discloses a motor
vehicle with a radiator having a catalytic coating, in which a
control unit with an associated sensor system controls operation of
the radiator and informs the user about the state or operation of
the radiator. The sensor system also has temperature sensors at
different locations in the cooling system. This publication does
not, however, describe securing the radiator against manipulation,
or disclose a method for detecting manipulation, for example by
means of temperature sensors.
[0006] Temperature-measuring devices for cooling water also have
sensors which measure the absolute temperature of the cooling water
after opening of the thermostat, which guides the cooling circuit
past the radiator for a certain time in the closed state after the
motor is started, and through the radiator after it is opened. One
disadvantage of this arrangement is that the characteristics of the
thermostat change over time, and an absolute measurement of the
cooling-water temperature is not suitable for detecting the
installation of a catalytically active radiator as opposed to a
conventional radiator.
[0007] One object on which the present invention, therefore, is to
provide a method and apparatus for detecting reliably the presence
of a prescribed heat exchanger, particularly a catalytically active
radiator in a motor vehicle.
[0008] This and other objects and advantages are achieved by the
method according to the invention which includes the following
method steps during operation of the motor vehicle:
[0009] (S1) observing the temperature of a heat-exchanger medium
and at the same time observing further current operationally
relevant parameters of the motor vehicle for a given time
window;
[0010] (S2) detecting an expected time gradient of the temperature
of the heat-exchanger medium;
[0011] (S3) detecting the current time gradient of the temperature
of the heat-exchanger medium; and
[0012] (S4) detecting the presence of a prescribed heat exchanger
by taking into account the expected and current time gradients.
[0013] In addition, the invention also includes an apparatus for
detecting the presence of a prescribed heat exchanger, in
particular a catalytically active radiator in a motor vehicle,
which includes: [0014] at least one heat exchanger with a
heat-exchanger medium of the motor of the motor vehicle; [0015] at
least one measuring device for measuring the temperature of the
heat-exchanger medium; and [0016] an evaluation device for
evaluating data and for detecting the presence of a prescribed heat
exchanger.
[0017] The idea on which the present invention is based involves
integrating a temperature sensor in a heat exchanger, such that the
temperature sensor can be used to measure a specific absolute
temperature gradient over time of the heat-exchanger medium in
specific operating states of the engine. When a heat exchanger is
manipulated, a different temperature gradient is measured, and an
evaluation algorithm performed to draw a conclusion regarding the
presence of a catalytically active radiator. This results in the
following advantages:
[0018] The relevant statutory regulations regarding exhaust-gas
standards and environmental protection can be satisfied by
establishing the presence of a catalytically active radiator by
measuring an absolute temperature gradient.
[0019] A change in the characteristics of the thermostats has no
effect on the measurement result.
[0020] Manipulations can be uncovered and economic loss can be
avoided.
[0021] The inventive apparatus provides further advantages:
[0022] An attempt to remove a temperature sensor from the apparatus
leads to irreversible damage to the sensor.
[0023] If the temperature sensor is cut out off a catalytically
active radiator which is no longer operable, or forcibly removed in
some other way (since it cannot be easily removed on account of the
inventive apparatus, and is fitted in the engine compartment, for
example to a coolant tube or to a conventional exchange radiator),
this is reliably identified by the inventive method.
[0024] The illegal installation of a conventional radiator instead
of a prescribed catalytically active radiator is therefore
prevented.
[0025] In one preferred embodiment, method step S1 comprises the
following substeps:
[0026] (S1-1) measuring values of the temperature of the
heat-exchanger medium in predefined time intervals and plotting the
time profile of these values; and
[0027] (S1-2) measuring values of the operationally relevant
parameters at predefined time intervals and plotting the time
profiles of these values.
[0028] The operating state of the motor vehicle in the time window
can thus be advantageously determined.
[0029] A further refinement of the invention provides for the
following the substeps in the method step S2:
[0030] (S2-1) comparing the plotted current operationally relevant
parameters with predefined values;
[0031] (S2-2) determining an associated current operating state in
accordance with this comparison; and
[0032] (S2-3) determining the temperature gradient expected in this
current operating state.
[0033] The operating states can advantageously be determined from
tables by means of stored data, and it is also possible to
determine the expected temperature gradient in a simple manner.
[0034] In one further embodiment, the current temperature gradient
is detected in method step S3 by taking into account the current
values of the temperature of the heat-exchanger medium plotted in
the time window.
[0035] Method step (S4) advantageously comprises the following
substeps:
[0036] (S4-1) comparing the current temperature gradient with the
expected temperature gradient;
[0037] (S4-2) taking into account this comparison result with
reference to a predefined threshold value; and
[0038] (S4-3) transmitting data signals when a prescribed heat
exchanger is present.
[0039] In a further refinement of the present invention, method
step S4 comprises the following substeps:
[0040] (S4-1) comparing the current temperature gradient with the
expected temperature gradient;
[0041] (S4-2) taking into account this comparison result with
reference to a predefined threshold value;
[0042] (S4-3) incrementing at least one counter in accordance with
the comparison result from substep (S4-2);
[0043] (S4-4) carrying out method steps (S1) to (S4-3) until a
predefined counter reading is reached; and
[0044] (S4-5) outputting data signals when a prescribed heat
exchanger is present.
[0045] The plausibility of the measurement results can therefore be
checked and the measurement results can, for example, be
transmitted to a so-called on-board diagnosis system by
advantageously carrying out the method more than once.
[0046] It is advantageous for another inventive embodiment to
provide for the time window to be determined to begin at a first
time when at least one operationally relevant parameter reaches a
predefined starting threshold value, and for the time window to be
determined to end at a second time when the same, or at least one
further operationally relevant, parameter reaches the same or a
further predefined ending threshold value.
[0047] In a further embodiment of the invention, the measuring
device of the apparatus has at least one temperature sensor for
measuring the temperature of the heat-exchanger medium; a holding
element for holding the temperature sensor; and a connection device
for connection to the evaluation device.
[0048] Furthermore, it is particularly advantageous for the holding
element to be connected to the heat exchanger in a non-releasable
manner, so that unauthorized removal is prevented in a simple
manner.
[0049] According to another embodiment of the invention the element
for holding the temperature sensor has a holder which corresponds
to said temperature sensor.
[0050] It is also advantageous for the temperature sensor to have a
predetermined breaking point, and to be connected to the holding
element such that it is rendered permanently inoperable after it
has been removed from the holding element.
[0051] The temperature sensor is expediently a constituent part of
an adapter of the connection device in this case.
[0052] It is particularly advantageous for the adapter and the
holding element to have corresponding fastening elements which are
designed such that they cannot be released following assembly,
since this provides an additional way of preventing
manipulation.
[0053] In a further embodiment of the invention, the evaluation
device has a memory device for storing values of time profiles of
measured values, a data memory for storing predefined threshold
values, operating state data and the like, and at least one
counter.
[0054] The evaluation device is advantageously a constituent part
of an on-board computer (ECU) of a motor vehicle.
[0055] The method allows a reliable conclusion to be drawn
regarding the positioning of the temperature sensor and therefore
whether a catalytically active radiator is present, by measuring
the temperature gradient in a predefined value range. In addition,
the inventive apparatus provides advantageous ways of preventing
manipulations.
[0056] Other objects, advantages and novel features of the present
invention will become apparent from the following detailed
description of the invention when considered in conjunction with
the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0057] FIG. 1 is a schematic graph that depicts time variation of
operationally relevant parameters of a motor vehicle during
operation;
[0058] FIG. 2 is a schematic block diagram of a representative
embodiment of the inventive apparatus;
[0059] FIG. 3 is a schematic view of a holding element according to
the invention, installed in a radiator; and
DETAILED DESCRIPTION OF THE DRAWINGS
[0060] FIG. 4 is a schematic perspective view of a connection
device according to the invention.
[0061] Unless stated otherwise, identical or functionally identical
parts and/or assemblies have the same reference symbols in all of
the figures of the drawing.
[0062] In FIG. 1, various profiles of operationally relevant
parameters of a motor vehicle are schematically illustrated against
a time axis t. Reference symbol 21 denotes vehicle speed which is
illustrated with a double-thick line. At a first time t1 the speed
rises above a threshold value S, and runs relatively constantly
within a time window tf until it falls to values below the
threshold value S at time t2. (This profile represents, for
example, a specific operating state of a motor vehicle, such as a
relatively long motorway journey.)
[0063] On account of the relatively high traveling speed, the
operating temperature of the vehicle engine (and therefore also the
temperature of its heat-exchanger medium, such as cooling water)
increases, the profile of said temperature of its heat-exchanger
medium being denoted by reference symbol 22 with a solid line. Due
to operation of the engine, this first temperature 22 of the
heat-exchanger medium increases in a known manner, with a delay
within the time window tf, which can be seen from the distance to
the first time t1 on the time axis t. This rise in temperature has
a gradient which is relevant for the operating state and is
illustrated by a straight gradient line 24 which forms a so-called
temperature gradient over time.
[0064] This temperature gradient is characterized by a specific
operating state of the motor vehicle. This operating state can be
described in the time window tf by specific operationally relevant
parameters, for example vehicle speed v in km/h, rotational speed n
of the engine in revolutions/min, exhaust-gas quantity in .DELTA.
mass/time, etc. For reasons of clarity, only the vehicle speed is
shown in FIG. 1.
[0065] Specific operating states can therefore be identified on the
basis of the known parameter values and associated expected
temperature gradients of the heat-exchanger medium can be
determined. For example, it is possible to predict the expected
rise in temperature of the heat-exchanger medium by means of the
exhaust-gas quantity and its temperature.
[0066] This temperature gradient is also a function of the location
(in the cooling circuit of the vehicle engine) at which the
heat-exchanger temperature is measured, in particular by where and
how an associated measuring device is installed. The heat-transfer
processes, which occur in this regard, with different heat-transfer
resistances, are known and do not need to be explained.
[0067] This is illustrated by the profile of a temperature 23 of a
second heat-exchanger medium, with the associated measuring device
being fitted, for example, on the outside of a coolant tube. In
this case, the temperature increases, after a delay, with a second
straight gradient line 25 in the same time window tf in the same
operating state as in the first temperature 22 of the
heat-exchanger medium. As can be seen, the second straight gradient
line 25 has a temperature gradient which differs from that of the
first straight gradient line 24, in this case with a lower
value.
[0068] The method according to the invention will now be described
with reference to FIG. 1.
[0069] At time t1, engine temperature first exceeds 85.degree. C.,
for example, which is treated as an entry criterion. If at least
one specific operationally relevant parameters exceeds a predefined
threshold value SW depending on a specific operating state, the
time window tf is started in a first method step S1.
[0070] The operationally relevant parameters and the temperature of
the heat-exchanger medium are observed within the time window tf in
a subsequent method step S2. That is, their values are measured and
stored at predefined time intervals, so that the value profile is
recorded, for example in a memory device of an associated
evaluation unit or in the on-board computer.
[0071] After the value falls below the same or a further predefined
threshold value SW (or after a specific time elapses, this time
being controlled, for example, by a timer which is started
simultaneously at time t1), the time window tf is ended in a method
step S3 at the second time t2.
[0072] In a subsequent method step S4, the observed operationally
relevant parameters allow an operating state to be determined and
therefore a temperature gradient which is expected in this
operating state to be detected. In a further method step S6, the
temperature gradient which is obtained in this way is compared with
the current temperature gradient which is detected from the
recorded values of the temperature of the heat-exchanger medium in
a method step S5.
[0073] This comparison provides a conclusion about the location at
which the values of the current temperature gradient have been
measured. If the value or the value range of the current
temperature gradient matches that of the expected temperature
gradient, a suitable heat-exchanger, for example, is present. If
the value range of the current temperature gradient is less than or
greater than that of the expected temperature gradient, either the
installed heat-exchanger is not suitable or a manipulated
heat-exchanger system is present. The current temperature gradient
can be higher, for example in a manipulated cooling system, if it
is heated in a manipulative manner in order to obtain higher
temperature gradients. However, the other criteria cannot be
maintained in this case, as a result of which detection is
nevertheless possible.
[0074] In order to check the plausibility of these detection
values, this method is repeated more than once in a further
embodiment of the invention, and a counter is incremented for each
detected comparison value up to a predefined value with each run
through the method.
[0075] The result of the detection is transmitted to the on-board
computer for further processing or indication purposes, for example
by means of a data bus inside the vehicle. Special indicators or
measures can be initiated when a manipulation has occurred.
[0076] FIG. 2 is a schematic block diagram of an exemplary
embodiment of the apparatus for carrying out the inventive method
according to the invention.
[0077] The apparatus 1 comprises an evaluation unit 13 to which a
measuring device 5 for measuring the temperature of a
heat-exchanger medium in a heat exchanger 2 is connected by means
of a connection device 8 and a line 12.
[0078] Further detection units 17, 18, 19, 20 for operationally
relevant parameters, for example rotational speed 17 of the engine,
engine temperature 18, exhaust-gas quantity 19, vehicle speed 20,
are connected to the evaluation unit 13. The detection units 17,
18, 19, 20 and the like can also be connected to an on-board
computer 14' which is connected to the evaluation unit 13 by means
of a data-transmission means 26 and therefore supplies the required
data values.
[0079] The evaluation unit 13 has at least one memory device 15 and
at least one counter 16. (It may also be provided with a timer, not
illustrated). The memory device 15 is used, inter alia, to store
recorded measured values; and the counter 16 is an event
counter.
[0080] The evaluation device 13 also has a data memory 27 which
contains predefined table values, threshold values and the like
which are used to determine the operating states and expected
values.
[0081] The evaluation unit 13 may be a constituent part of an
on-board computer 14, as is indicated symbolically by a double
dot-and-dash line.
[0082] The measuring device 5 has a holding element 6 with a holder
7 for holding a temperature sensor 10, as illustrated in FIG. 3.
The holding element 6 is designed such that it is installed in the
heat exchanger 2, for example in an intermediate space 4 between
lamellae 3. The holding element 6 is preferably stuck in in such a
way that it damages the heat exchanger 2 when an attempt is made to
remove it. Other fastening options are also feasible.
[0083] The temperature sensor 10 is located in an adapter 9 of the
connection device 8, as shown in FIG. 4. The temperature sensor 10
and the holder 7 of the holding element 6 are of corresponding
shape and dimensions.
[0084] The adapter 9 is equipped with fastening elements 11 (for
example flexible retaining fingers with barbed hooks), which,
together with corresponding fastening elements (not illustrated) on
the holding element 6, form a connection which cannot be released
following assembly. Improper removal is therefore effectively
prevented.
[0085] In addition, in one embodiment, the temperature sensor 10 is
adhesively bonded in the holder 7 of the holding element 6 such
that it is rendered inoperable for example by means of a
predetermined breaking point, when an attempt is made to remove
it.
[0086] Although the present invention has been described with
reference to preferred exemplary embodiments above, it is not
restricted to these but can be modified in a variety of ways. For
example, it is feasible for the memory device 15, the counter 16
and a timer to be constituent parts of the on-board computer. It is
also feasible for the inventive method to be used for the advance
detection of functional faults in heat-exchanger systems. Finally,
the data memory 27 may also have wireless connecting devices to
external data memories, for example via satellite connection. It
may also be a CD-ROM or DVD device.
[0087] The foregoing disclosure has been set forth merely to
illustrate the invention and is not intended to be limiting. Since
modifications of the disclosed embodiments incorporating the spirit
and substance of the invention may occur to persons skilled in the
art, the invention should be construed to include everything within
the scope of the appended claims and equivalents thereof.
* * * * *